In automotive systems an alternator is driven by a combustion engine in order to provide electrical power. Modern systems make use of integrated circuits for regulating alternator output voltages. Basically the behavior of a regulator depends on the output voltage but also takes into account the status of the engine. The speed of the engine is an important indicator. Especially during the start up phase and also in low speed conditions, measurements of the engine's speed are of high interest. These measurements can be carried out either with external sensors or by using phase signals often obtained directly from the alternator. External sensors are accurate but very expensive, so preferred solutions are implemented in an on-chip fashion detecting the phase signals.
Conventional systems often suffer from the disadvantageous accuracy that is achieved with the on-chip solutions. Other conventional systems achieve higher accuracy, however at the price of high reaction times, so conventional controller systems are too slow to achieve an efficient control of the excitation current of an alternator and the alternator output voltage.